Question

How do you find the square root of 81/16?

Answer 1

`= color(blue)(9/4`

Explanation:

`sqrt (81/16)`

We simplify `81` and `16` by prime factorisation (expressing a number as a product of its prime factors).

• `sqrt (81) = sqrt (3 * 3 * 3 * 3 ) = sqrt ( 9 * 9 ) = sqrt (9^2) = color(blue)(9`

• `sqrt (16) = sqrt (2 * 2 * 2 * 2 ) = sqrt ( 4 * 4 ) = sqrt (4^2) = color(blue)(4`

So, `sqrt (81/16) = color(blue)(9/4`